Could anyone explain to what 我三谁了 mean in
我也不知道,我刷四绝朋友告诉我有人刷喇叭骂我小三,我不知道我怎么就小三了,我三谁了?!
I know that the whole sentence more or less means "I don’t know, my best friend told me that someone used the world speaker to scold me as a mistress, to scold me as a mistress, .......?!
What does 我三谁了 exactly mean?
It seems to be a very easy to understand sentence but I just cannot understand the 三 there. If I'm I'm taking a guess I would say that it's "Who is the third?" but if it's that then I have a hard time understanding it inside the sentence.